---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/420026#article
headline: "420026: Knowledge source bad gateway"
url: https://www.twilio.com/docs/api/errors/420026
inLanguage: en
dateModified: 2026-07-29T18:16:50.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 420026: Knowledge source bad gateway

Log Type: TWILIO

Log Level: ERROR

## Description

The web crawler received a `502 Bad Gateway` response when attempting to access the target URL during knowledge ingestion. The gateway or proxy server received an invalid response from an upstream server.

### Possible causes

* The target site's proxy or load balancer received an invalid response
* Upstream server failures or misconfigurations
* CDN or reverse proxy issues
* Network routing problems
* Temporary gateway or infrastructure issues

### Possible solutions

* Verify the target URL loads correctly in a web browser
* Check if the target site is experiencing infrastructure or CDN issues
* If the error is temporary, the crawler will retry on the next scheduled crawl
* For persistent errors, contact the target site administrator or hosting provider
* Consider using a different URL or CDN endpoint, if available
* Review the knowledge source error details in the Twilio Console